Tissue resection bander and related methods of use

ABSTRACT

A tissue resection cap assembly configured to be secured to the distal end of an elongated medical device, such as an endoscope, and a method for resecting tissue. The cap assembly may include a cap structure comprising a working channel and a resection device channel, wherein the resection device channel extends inside the cap structure to a resection device track positioned substantially around the working channel adjacent the distal end of the cap structure. The resection device channel is adapted to direct a resection device from the working channel of the endoscope to the resection device track. The cap assembly further includes one or more ligation bands on the outside surface of the cap structure and a trigger line for deploying the ligation bands from the distal end of the cap structure. The method includes deploying a ligation band around tissue and using a resecting loop to cut the tissue.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority to U.S. provisional patentapplication No. 61/580,819, filed Dec. 28, 2011, the disclosure of whichis hereby incorporated herein by reference. The subject matter of thisdisclosure is related to the subject matter of U.S. provisional patentapplication No. 61/552,326, filed Oct. 27, 2011, the disclosure of whichis hereby incorporated herein by reference.

DESCRIPTION OF THE INVENTION

1. Field of the Invention

This disclosure relates generally to systems and methods for resectingtissue. More particularly, certain embodiments of the claimed inventionrelate to systems for endoscopic mucosal resection.

2. Background of the Invention

Organ walls may be composed of several layers: for example, the mucosa(the surface layer), the submucosa, the muscularis (muscle layer), andthe serosa (connective tissue layer). In gastrointestinal, colonic, andesophageal cancer, small polyps or cancerous masses may form along themucosa and often extend into the lumens of the organs. Conventionally,that condition has been treated by cutting out and removing a portion ofthe affected organ wall. This procedure, however, may cause extensivediscomfort to patients, and poses health risks. Recently, physicianshave adopted a minimally invasive technique called endoscopic mucosalresection (EMR), which removes the cancerous or abnormal tissues(polyps) or normal tissues, while keeping the walls intact.

EMR is generally performed with an endoscope, which is a long, narrowtube equipped with a light, an imaging system such as a video camera,and channels to receive other instruments. During EMR, the endoscope maybe passed down the throat or guided through the rectum to reach tissuein the affected organ or otherwise targeted tissue. The distal end ofthe endoscope, further equipped for example with a cap, may be guidedtowards the abnormality. Once there, a suction pump attached to the tubemay be started to draw the abnormality towards the endoscope cap. Whenthe tissue is sufficiently drawn into the cap, a wire loop, whichextends through a working channel of the endoscope, may be closed aroundthe tissue, resecting it from the organ wall. Subsequently, excisedtissue may be extracted by, e.g., the vacuum, for examination ordisposal.

Certain polyps, such as pedunculated polyps, may be characterized by astalk attached to the mucosal layer. Drawing such polyps into the capwithout drawing in any other tissue is readily accomplished. Certainother polyps, such as sessile polyps, however, may exhibit a broad baseand may lay flat on the mucosal surface, devoid of a stalk. It can bedifficult to grasp these polyps without drawing in a part of themuscularis layer.

To overcome this problem, saline solution is typically injected beneaththe target tissue to raise the mucosal tissue and to create a bufferlayer. The raised tissue can then readily be severed, for example with aresection loop, often in several segments (segmental resection)depending on the size and location of the tissue.

In addition, the depth of the cut into the tissue is critical. Asdiscussed above, if the cut is too deep, the muscularis layer may beinjured, which may further cause a perforation. Conversely, a cut tooshallow may not remove enough of the affected tissue and therefore mayrequire additional procedures or worse, contribute to the development ofmetastatic cancer. Typically, more than 2 mm of cancerous tissueclearance is required to assure complete removal. EMR, as performed withconventional devices and methods, may result in complications such asperforation, bleeding, and/or strictures.

There exists a need for an improved resection loop device that improvesthe speed and accuracy of the procedures desired to be performed.

SUMMARY OF THE INVENTION

Embodiments of the present disclosure provide devices and methods forresecting undesired tissue from a patient's body using a minimallyinvasive surgical system.

In accordance with an aspect of the present disclosure, a tissueresection cap assembly for resecting tissue from a body is described.The cap assembly may be configured to be coupled to the distal end of anelongated medical device having a working channel, such as an endoscope,guide tube or the like. The cap assembly may include a cap structurecomprising a proximal end, a distal end, an outside surface, and aworking channel extending from the proximal end to the distal end; atleast one ligation band, for example an elastic band, positioned on theoutside surface of cap structure; and a trigger line for deploying theligation band(s) from the distal end of the cap structure. The capstructure further comprises a resection device channel and a resectiondevice track in communication with the resection device channel. Aproximal end of the resection device channel is adapted forcommunication with a working channel of the endoscope or other elongatedmedical device. The resection device channel may extend distally to theresection device track adjacent the distal end of the cap structure. Theresection device track may substantially surround the working channel ofthe cap structure adjacent the distal end of the cap structure.

In various embodiments, the cap structure may comprise a first cap and asecond cap. The first cap may include a distal end having a firstopening, and the second cap may include a distal end having a secondopening. The first cap may define the resection device channel. Thesecond cap may be configured to receive at least a portion of the firstcap. A distal portion of the first cap and a distal portion of thesecond cap may cooperate to define the resection device track forreceiving a distal portion of a resection device, which may be aresection loop.

In various embodiments, the device may include one or more of thefollowing additional features: the resection device track may bedisposed in a plane parallel to a plane of the second opening; theresection device track may extend at an angle to the resection devicechannel; the resection device channel may further include a resectionwire lumen positioned inside the first cap; the first cap may define theworking channel of the cap structure, extending from the distal end tothe proximal end of the first cap; the resection device channel may beformed of a flexible wall configured to collapse the resection devicechannel when a resection device is not present in the resection devicechannel; a portion of the resection device channel may be configured toprevent distal movement of a sheath associated with a resection device;the cap assembly may be configured to bend or pivot relative to thedistal end of the endoscope; a portion of the resection device channelmay be defined by an outer wall of the first cap; the resection devicechannel may further include a cylindrical section disposed within thefirst cap; the distal end faces of the first and second caps may beangled relative to a longitudinal axis of the cap assembly; and theresection device may comprise a resection loop that may further comprisean electrocautery tool.

A further aspect of the present disclosure includes a resection devicecomprising a first part and a second part. The first part defines aresection device channel, wherein the first part includes a distal endhaving a first opening. The second part is configured to receive atleast a portion of the first part, wherein the second part includes adistal end having a second opening, wherein a distal portion of thefirst part and a distal portion of the second part cooperate to define aresection device track for receiving a resection device. The resectiondevice further includes at least one ligation band positioned on theoutside surface of the second part and a trigger line for deploying theligation band from the distal end of the second part.

A further aspect of the present disclosure includes a method ofresecting tissue. The method may include attaching a cap assembly to thedistal end of an endoscope or other elongated medical device. The capassembly may include a cap structure comprising a proximal end, a distalend, an outside surface, and a working channel extending from theproximal end to the distal end; at least one ligation band positioned onthe outside surface of cap structure; and a trigger line for deployingthe ligation band(s) from the distal end of the cap structure. The capstructure may further comprise a resection device channel and aresection device track in communication with the resection devicechannel. A proximal end of the resection device channel may be adaptedfor communication with a working channel of the endoscope. The resectiondevice channel may extend distally to the resection device trackadjacent the distal end of the cap structure. The resection device trackmay surround the working channel of the cap structure adjacent thedistal end of the cap structure. The method further includes positioningthe cap assembly adjacent to tissue to be resected and drawing tissue,for example with suction, within the cap assembly. The method maycomprise actuating the trigger line to deploy a ligation band around thetissue, and then, if desired, actuating the resection device to cut thetissue. Alternatively, the method may comprise actuating the resectiondevice to close the resection device loop around the tissue, evaluatingthe ensnared tissue, and then either further actuating the resectiondevice to cut the tissue or opening the resection device loop to releasethe tissue. If the tissue is released, the method may further compriseactuating the trigger line to deploy a ligation band around the tissue,and then, if desired, again actuating the resection device to cut thetissue.

In various embodiments, the step of attaching the cap assembly to thedistal end of the endoscope may include aligning the resection devicechannel with a working channel of the endoscope. After actuating thetrigger line to deploy a ligation band and prior to actuating theresection device to cut the tissue, suction may be released to allowconfirmation of proper positioning of the resection device.

The cap assembly may further comprise a channel for allowing the triggerline to extend from a working channel of the cap structure to theoutside surface of the cap structure without having the trigger lineextend through a resection loop of the resection device.

Additional objects and advantages of the claimed invention will be setforth in part in the description, which follows, and in part will beobvious from the description, or may be learned by practice of theinvention. The objects and advantages of the invention will be realizedand attained by means of the elements and combinations particularlypointed out in the appended claims.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and explanatory onlyand are not restrictive of the invention, as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate exemplary embodiments of thepresent disclosure and together with the description serve to explainthe principles of the disclosure.

FIG. 1A is an exploded view of an EMR cap assembly, according to anembodiment of the present disclosure.

FIG. 1B is a sectional view of the EMR cap assembly of FIG. 1A.

FIG. 1C is an end view of the EMR cap assembly of FIG. 1A.

FIG. 2A is a schematic of an inner cap, according to embodiments of thepresent disclosure.

FIG. 2B is an end view of the inner cap of FIG. 2A.

FIG. 2C an isometric view of the inner cap of FIG. 2A taken from theproximal end.

FIG. 2D is an isometric view of the inner cap of FIG. 2A taken from thedistal end.

FIGS. 3A-3C illustrate various embodiments of the inner cap, accordingto embodiments of the present disclosure.

FIG. 4 illustrates the EMR cap assembly of FIG. 1 viewed from the distalend.

FIG. 5 illustrates an exemplary resection device incorporating the EMRcap assembly of FIG. 1, according to embodiments of the presentdisclosure.

FIGS. 6A-6F illustrate an exemplary method for resecting a tissue from amucosal wall using the EMR cap assembly of FIG. 1, according toembodiments of the present disclosure.

DESCRIPTION OF THE EMBODIMENTS

Reference will now be made in detail to embodiments of the presentdisclosure, an example of which is illustrated in the accompanyingdrawings. Wherever possible, the same reference numbers will be usedthroughout the drawings to refer to the same or like parts. The term“distal” refers to the end farthest away from a medical professionalwhen introducing a device in a patient. By contrast, “proximal” refersto the end closest to the medical professional when placing a device inthe patient.

Overview

Embodiments of the present disclosure relate to systems and methods forresecting and extracting foreign or undesirable objects from a patient'sbody. For example, the device may remove cancerous polyps or lesionsfrom the mucosal walls of the colon, esophagus, stomach, duodenum, orany other suitable location. It should be understood that the resectiondevice may perform the functions of both resecting and retrieving, butfor convenience, the term “resection device” will be used throughoutthis application.

The resection device may include an end-effector, such as, e.g., an EMRcap assembly, fitted on the distal end of any tube, such as anendoscope, for ensnaring, cauterizing, and extracting tissue such as apolyp. The EMR cap assembly may include a working channel, as well as aresection loop channel aligned with and inserted into the workingchannel. The EMR cap assembly may further include a track along itsdistal circumference in communication with the resection loop channel,such that a resection loop extending from the resection loop channelslides into the track when the resection loop is in an open position. Inthis position, the resection loop is parallel to the opening of the EMRcap assembly. When the EMR cap assembly is placed over an undesiredtissue, tissue may be drawn into the working channel, for example bysuction. One or more ligation bands may then be deployed from the distalend of the EMR cap assembly, for example by causing a trigger line to bepulled proximally, such that the ligation band is released andconstricts around the tissue. This banding action may form a pseudopolyp. The suction may then be released, and the proper positioning ofthe resection loop may be confirmed, for example by visualizing the sitewith the endoscope. This can include a confirmation check that nomuscularis is within the area to be resected by the resection loop. Theresection loop may then be pulled proximally, reducing the diameter ofthe loop in the track and engaging the drawn tissue. Subsequently, thetissue may be cauterized and extracted. Because the resection loopextends substantially around the EMR cap assembly's distal opening, theoperator can easily place the resection loop around the tissue tocapture and cauterize it. Moreover, only the mass drawn into the EMR capassembly's working channel is resected, ensuring that deeper layers ofthe organ wall are not affected.

In the following sections, embodiments of the present disclosure will bedescribed using an exemplary body organ—the esophagus. It will beunderstood that this choice is merely exemplary and that the device maybe utilized in any other suitable organ, such as the colon, duodenum,stomach, or any other organ that may be subject to polyps, lesions,stones, and the like.

Exemplary Embodiments

Exemplary EMR Cap Assembly

FIGS. 1A-1C presents three views of an EMR cap assembly 100 forresecting polyps, lesions, or otherwise unwanted tissue from, e.g., themucosal walls of organs according to embodiments of the presentdisclosure. EMR cap assembly 100 is configured to be secured to a distalportion of an endoscope for advancing towards a target location with apatient. Particularly, FIG. 1A is an exploded view, FIG. 1B is asectional view, and FIG. 1C is an end view of EMR cap assembly 100.These figures will be commonly referenced to describe the structure andfunction of the EMR cap assembly 100. The EMR cap assembly 100 may bedetachably connected to the distal end of any flexible or rigid tube,such as an endoscope used for colonoscopy, resectoscopy, cholangioscopy,or mucosal resection.

EMR cap assembly 100 includes a cap structure comprising an inner cap102 and an outer cap 104. The inner and outer caps 102, 104 may behollow elongate members with distal ends 106, 107, respectively, andproximal ends 108, 109, respectively, with lumens 110, 111,respectively, extending between the respective distal and proximal ends.The outer cap 104 fits over the inner cap 102, and this completeassembly is attached to a tube (not shown).

The inner cap 102 and outer cap 104 may have substantially circularcross-sections or cross-sections similar to those of body cavities.Where required by given applications, the EMR cap assembly 100 mayinclude elliptical, semi-circular, rhombic, rectangular, or othernon-circular profiles. Moreover, the diameter of the EMR cap assembly100 may vary based on the size of the body lumens in which it operates.For example, if the EMR cap assembly 100 is inserted through theurethra, the diameter of the inner and outer caps may be very small.Conversely, if the device is inserted through the rectum, the diameterof the inner and outer caps may be larger.

Any suitable material may form inner and outer caps 102, 104. Forinstance, rigid or semi-rigid materials such as metals (includingmaterials such as nitinol), polymers, resins, or plastics such aspolycarbonate or polyethylene may be used. Further, a biocompatiblematerial that does not irritate the body lumens may form a coating orlayer over the outer surface of EMR cap assembly 100.

As can be seen in FIGS. 1A-1C, the cap assembly 100 further includes aplurality of ligation bands 122, 124, 126, 128 positioned on the outsidesurface of the outer cap 104. The cap assembly 100 further includes atrigger line 140 for deploying the ligation bands 122, 124, 126, 128from the distal end 107 of the outer cap 104.

The ligation bands, trigger line, and configuration of the outer cap fordeployment of the ligation bands may take any suitable form. Examples ofligation bands, trigger lines, and cap configurations for deployment ofligation bands are described and illustrated in U.S. Pat. Nos.5,968,056; 5,976,158; 5,853,416; 6,077,275; 5,269,789; 5,398,844;6,235,040; 5,972,009; 5,913,865; 5,857,585; 7,063,709; 6,471,987;6,632,228; RE 36629 and U.S. Published Patent Application Nos.2008-0097478, 2011-0077666 and 2008-0091218; the disclosures of thesepatents and patent applications are hereby incorporated herein byreference. For example, the cap assembly 100 may include a singletrigger line 140 that is wrapped around the ligation bands 122, 124,126, 128 in a manner as described in U.S. Pat. No. 5,857,585, to allowfor sequential deployment of the bands 122, 124, 126, 128 by actuationof the trigger line 140. The inner cap 102 and outer cap 104 may betransparent in whole or in part to improve the operator's field ofvision, for example as described in U.S. Pat. No. 5,853,416. The distalend 107 of the outer cap 104 may have slots with different slot depths,and the trigger line may have suitable retentions elements (e.g., knots,etc.), as described in U.S. Pat. Nos. 6,235,040 and 5,913,865. The outercap may have ridges for lifting the ligation bands 122, 124, 126, 128off of the trigger line 140 and/or for promoting rolling of the ligationbands 122, 124, 126, 128, for example as described in U.S. Pat. No.7,063,709. The ligation bands may be comprised of any suitable elasticmaterial or may be comprised of one or more less elastic materials,components or sections. For example, in some embodiments, the ligationbands may comprise filament loops which can be cinched around tissue.

The ligation bands 122, 124, 126, 128 are configured such that when thetrigger line 140 is actuated, for example by an operator causing thetrigger line 140 to be pulled from a proximal end, each band issequentially deployed off of the distal end 107 of the outer cap 104.When positioned on the outer surface of the outer cap 104, the ligationbands 122, 124, 126, 128 are in a stretched condition. A first actuationof the trigger line 140 causes the first ligation band 122 to bedeployed off of the distal end 107 of the outer cap 104. When thishappens, the first ligation band 122 constricts toward its relaxed,unstretched condition. When this deployment is performed with tissueinside of the working channel of the cap structure, the constriction ofthe ligation band 122 around the tissue forms a pseudo polyp. The use ofmultiple ligation bands 122, 124, 126, 128 may allow the device to berepositioned for capturing additional tissue with sequential deploymentof the bands without having to withdraw the device from the patient.Thus, after repositioning, a second actuation of the trigger line 140may cause the second ligation band 124 to be deployed off of the distalend 107 of the outer cap 104. Then, after further repositioning, a thirdactuation of the trigger line 140 may cause the third ligation band 126to be deployed off of the distal end 107 of the outer cap 104, and,after further repositioning, a fourth actuation of the trigger line 140may cause the fourth ligation band 128 to be deployed off of the distalend 107 of the outer cap 104.

It will be appreciated by persons of ordinary skill in the art that thetrigger line 140 extends proximally from the distal end 107 of the outercap 104, through the inside of the cap assembly 100, and through theendoscope toward the operator of the device. For clarity ofillustration, the portion of the trigger line 140 that extends along theinside of the cap assembly 100 is not shown in FIG. 1A.

As can be seen in FIG. 1B, the cap assembly 100 may comprise a channel142, 144 for allowing the trigger line 140 to extend from a workingchannel 110 of the first cap 102 to the outside surface of the secondcap 104 without having the trigger line 140 extend through a resectionloop of the resection device (described below). In this illustratedembodiment, the channel 142, 144 comprises a first channel segment 142that extends through the wall of the first cap 102 and a second channelsegment 144 that extends through the wall of the second cap 104 to thedistal end 107 of the second cap 104. Because the trigger line 140 doesnot extend through a resection loop of the resection device (describedbelow), the resection loop can be deployed without ensnaring the triggerline 140.

As can be further seen in FIG. 1B as well as in FIG. 1C, the inner cap102 may have a guiding tab 146 with a bore 148 through which the triggerline 140 extends, thereby keeping the trigger line 140 generally alongthe inside of the wall of the inner cap 102. For clarity ofillustration, the trigger line 140 is not shown in FIG. 1C.

A detailed discussion of inner cap 102 and outer cap 104 follows, inconnection with FIGS. 2-4.

FIG. 2 illustrates four views of inner cap 102. More particularly, FIG.2A is a schematic view, FIG. 2B is an end view, FIG. 2C is an isometricview taken from proximal end 108, and FIG. 2D is an isometric view takenfrom distal end 106. Lumen 110 of inner cap 102 includes a workingchannel 202 and a resection device channel or resection loop channel204. The dimensions of these channels may vary considerably from oneapplication to another. For example, in procedures where a resected massis extracted through the tube, working channel 202 may be larger thanresection loop channel 204. Otherwise, where no need for removal of aresected mass is presented, resection loop channel 204 may be largerthan working channel 202. Moreover, working channel 202 may includenumerous other channels to carry desired instruments, such as cameras,light sources, and other endoscopic instruments.

As illustrated in FIG. 2A, resection loop channel 204 extends fromproximal end 108 to distal end 106 of inner cap 102. Moreover, aproximal portion of channel 204 may include a hollow or lumenal section206 (FIG. 2C), and this section may lead to a flared section 208 (FIGS.2C and 2D) towards the cap's distal end 106.

Section 206 may accommodate an outer sheath of a resection device orresection loop (not shown). In one embodiment, the diameter of section206 is substantially equal to or smaller than the diameter of theresection loop sheath. Moreover, section 206 may taper distally suchthat the diameter of the section's distal end is smaller than thediameter of the sheath, preventing the sheath from extending beyond thedistal end of section 206. Alternatively, section 206 may have a uniformdiameter from its proximal end to its distal end, optionally including aledge 210 on its distal end. The ledge 210 extends radially inwards,reducing the distal end's diameter to equal to or less than the sheath'sinner diameter, thereby stopping the sheath from extending distallybeyond the distal end of section 206. The shaded portion in FIG. 2Billustrates ledge 210.

It will be understood that instead of the ledge, any other structure maybe employed to reduce the diameter of the cylindrical portion's distalportion. For example, some configurations may include actuatableprotrusions, or barbs extending inwards in parallel to the distal end ofthe section 206.

Flared section 208 does not necessarily flare out radially in alldirections; instead, it may flare out parallel to a portion of the cap'sinternal wall. In some embodiments, however, section 208 may fully flareout.

A portion or the entire resection loop channel 204 may be in contactwith the inner wall. Alternatively, resection loop channel 204 may bepositioned adjacent the inner wall. In this embodiment, a support block212 may connect resection loop channel 204 with the inner wall. It willbe understood that the resection loop channel's placement within lumen110 may vary without departing from the scope of the present disclosure.

In some instances, section 206 may not abut the inner wall of the innercap 102. Instead, it may be slightly spaced from the inner surface.Flared section 208, however, may make contact with the inner wall.Moreover, the width of flared section 208 may be smaller than or equalto the diameter of section 206. To maintain this width and to increasethe working channel's area, flared section 208 may curve toward theinner wall. FIG. 2A illustrates this embodiment.

Alternatively, the width of flared section 208 may be greater than thediameter of section 206. In this case, the portion of the resection loopchannel wall in contact with working channel 202 may extend parallel tothe longitudinal axis of section 206, while the portion of the channelwall closer to the inner wall may flare out radially to contact theinner wall. FIGS. 3A and 3B illustrate this embodiment. Compared to FIG.2A, it is evident that this embodiment features a broader resection loopchannel 204, while the working channel 202 space is reduced.

In an alternative embodiment, the portion of the inner cap 102 abuttingflared section 208 may be cut out or removed, leaving the resection loopchannel with a partial wall. Outer cap 104 abuts flared section 208(FIG. 1A) forming the remaining wall for resection loop channel 204.

The degree of angular displacement of the distal end of flared section208 may vary based on numerous factors, such as tensile strength of theresection loop, size of resection loop, or diameter of inner cap 102. Itwill be understood, however, that flared section 208 may be sufficientlybroad and wide to allow the resection loop to open completely into anactive position. “Active position” refers to a position in which theresection loop is completely open and its loop diameter is approximatelyequal to or slightly smaller than or slightly greater than the diameterof inner cap 102.

Alternatively, resection loop channel 204 may not have a cylindricalsection, and instead it may begin flaring from the proximal end 108 ofthe inner cap 102 (shown in FIG. 3C). It will be understood that theshape of flared section 208 may vary without departing from the scope ofthe present disclosure. For example, the flare's cross-section may havea generally “U” shape, “V” shape, semicircular shape, semi-ellipticalshape, square shape, rectangular shape, or any suitable shape.

In FIG. 2, resection loop channel 204 is permanently fixed in the innercap and in the gap between the inner and outer caps. In anotherembodiment, however, resection loop channel 204 may be detachablyconnected to working channel 202. When the resection loop is not in use,resection loop channel 204 may be removed. In another embodiment, theresection loop channel 204 may be collapsible, i.e., formed of aflexible membrane. When the resection loop is not inserted in the cap,the flexible membrane may rest against the inner wall of inner cap 102(converting the complete lumen into working channel 202). When theresection loop is inserted, it may push the flexible member away fromthe inner wall and into the working channel 202. Once the lesion isresected, the resection loop may be retracted, and the flexible membermay return to its original position (against the inner wall of inner cap102). Detachably connecting resection loop channel 204 or incorporatingit with a flexible wall increases the working channel 202 width,allowing the resection device to extract large resected pieces.

Outer cap 104 includes a general cross-sectional shape similar to thatof inner cap 102. An inner diameter of outer cap 104, however, is largeenough to fit around inner cap 102. When fit over inner cap 102, distalend 107 of outer cap 104 extends distally beyond inner cap 102. Thespace between the distal ends of inner cap 102 and outer cap 104 mayform a track for guiding the resection device or resection loop, such asthe resection device track or resection loop track 112 shown in FIG. 1B.

FIG. 4 illustrates the track in detail. As shown, track 112 includes thecircular-shaped distal surface of inner cap 102, and the inner walls ofouter cap 104 extending distally beyond inner cap 102. Further, thetrack may be sufficiently wide and high to slidably receive a resectionloop, such as resection loop 402. Moreover, the distal surface of outercap 104 may include a support structure 404 such as an edge, ridge,ledge, or rail extending circumferentially inward such that the supportstructure is wide enough to cover the proximal surface of inner cap 102,thus providing a track surrounded on three sides (top, bottom, and outeredge) and open on one side (inner edge). Alternatively, supportstructure 404 may include multiple equidistant protrusions extendingtowards the lumen 110. These support structures allow the resection loop402 to rest parallel to the distal opening of the EMR cap assembly 100when the resection loop 402 is extended into track 112. It will beunderstood that any other structure to maintain the resection loop 402within track 112 is conceivable and within the scope of the presentdisclosure.

In one embodiment, the distal openings of both inner cap 102 and outercap 104 may lie perpendicular to the longitudinal axes of the caps.Alternatively, the distal openings may slant at an acute angle to thelongitudinal axes. Because tissues may be present on the esophagealwalls, out of the direct path of an endoscope advancing through thatorgan, the slanted distal opening provides a greater surface areacontact between the EMR cap assembly's distal opening and the tissues.It will be understood that the slant angle may vary based on the organor the procedure. For example, a narrower body organ, such as theesophagus, may call for a distal opening slanted at a greater angle thanfor wider body organs, such as the stomach.

Resection loop channel 204, along with track 112, forms a path for theresection loop 402. The loop, enclosed within a sheath, may be insertedfrom the proximal end 108 into the resection loop channel 204. Thesheath may extend up to the distal end of section 206. From there, theresection loop may be advanced distally into the flared section 208.Because the channel 204 is flared, the resection loop is providedsufficient space to expand into the active position. Moreover, flaredsection 208 merges with track 112, allowing the resection loop to slideinto track 112 in its active position, such that the loop rests alongthe circumference of the inner cap's distal opening, between the innerand outer cap.

Pushing the resection loop distally can place it in the active positionon track 112, while pulling the resection loop proximally closes theresection loop. Because the resection loop lies in track 112, it closesessentially parallel to the distal opening of the EMR cap assembly. Thisresection loop configuration allows the EMR cap assembly to grasp andhold flat tissues.

As described in this disclosure, the resection loop is a wire loopdevice used to cauterize a lesion, polyp, or any other tissue. Thecross-sectional diameter of the wire may vary according to theapplication. In an embodiment, the resection loop may comprise aresecting hook comprising an generally arcuate shape surrounding aportion of the cap. Further, the resecting hook may have anycross-sectional geometry. For example, the cross-section may be flat,round, or triangular. In another embodiment, the resection loop may be acauterizing resection loop that is energized by passing electricalenergy through the loop. Moreover, the electrical energy may besufficient to cauterize the tissue swiftly. The cauterizing resectionloop may be mono-polar, where high frequency electrical current ispassed from a single electrode and the patient's body serves as groundor bipolar where high frequency electrical current is passed through thetissue from one electrode to another. It will be understood that insteadof electrical energy, any other form of energy now known or known in thefuture may be supplied to the resection loop to resect the tissue fromthe organ wall. For example, high heat energy may be supplied, enablingthe resection loop to burn the tissue from the organ wall. Similarly,other energy sources, e.g., RF, ultrasonic, laser and cryogenic, may beconsidered without departing from the scope of the present disclosure.In addition, the disclosed EMR cap assembly may be utilized with anysuitable cutting device known to those skilled in the art, such as, forexample, an energy actuated wire loop, a wire loop with no actuation, ahook, a knife, a blade, etc., all with or without activation.

The inner and outer caps may be detachably connected, permanentlycoupled, or formed into an integral component. Detachable connectionsmay include, but are not limited to, snap fit assembly, screw fitassembly, luer-lock assembly, or force lock assembly. For example, aproximal portion of the outer cap's inner wall may include one or morescrew threads, while the corresponding portion of the inner cap's outerwall may include corresponding screw threads. After placing outer cap104 over inner cap 102, the outer cap 104 may be rotated to engage thescrew threads of the inner and outer caps 102, 104. In another instance,inner cap 102 may include one or more protrusions along its outer wall,while outer cap 104 may include corresponding grooves on its inner wall.The protrusions may engage with the grooves when outer cap 104 is placedover inner cap 102, snap fitting them in place. It will be understoodthat other temporary or permanent connection techniques are well withinthe scope of the present disclosure. In one example embodiment, theouter and inner caps are permanently assembled together with a spacebetween them forming the track. In another example embodiment, the outerand inner caps are capable of being assembled together at the time ofattaching the cap assembly to the endoscope. For example, the outer andinner caps may be capable of squeezing a membrane between them whenattached together (e.g., by threading or snap fit) to create areleasable connection to the endoscope.

Permanent connection methods include gluing or spot-welding, dependingon the cap material. Alternatively, these elements may be permanentlysealed with a high-strength adhesive, such as epoxy. To form a singlecomponent, the EMR cap assembly may be made of a single component thatincludes a resection loop channel merging into a track parallel to itsdistal opening. The EMR cap may be formed as a single component bymolding, lithography or any other suitable manufacturing technique.

The diameter of EMR cap assembly 100 may be configured to match therequirements of particular applications. In general, a uniform diameteralong the length of the device may be preferred for most applications.In situations where tissues are small or when the body cavity is verynarrow, a tapered EMR cap assembly may be preferred. Conversely, flaredor tapered EMR cap assemblies may be utilized when the tissues are largeor the body cavity is wide.

The distal edge of the cap assembly, e.g., around the opening, may belayered or coated with a pliant material like silicone to enable abetter vacuum seal between the cap and tissue.

The following section describes a resection device that may implementthe EMR cap assembly 100 for conducting endoscopic mucosal resection.

Exemplary Resection Device

FIG. 5 is a perspective view of a resection device 500 for cutting andextracting an undesired mass through an incision or a natural bodyopening. The device 500 includes an elongate tube 502, such as anendoscope, with a distal end 504, a proximal end 506, joined by a lumen508. Proximal end 506 may be coupled to a handle 510, while distal end504 is coupled to EMR cap assembly 100. The tube further includes one ormore internal channels (not shown) having proximal and distal endopenings.

Tube 502 may have a cross-sectional configuration adapted according to adesired body lumen. In the illustrated embodiment, tube 502 may includea generally circular cross-section, with a generally circular hollowinterior lumen. Further, the tube 502 may have a uniform diameter or maybe tapered at the distal end to allow convenient insertion within thebody.

Depending upon the particular implementation and intended use, thelength of tube 502 may vary. For example, tube 502 may be a fewcentimeters or less where a shallow body cavity or organ is involved.For long cavities or deeper organs such as the bowel or intestine, tube502 may be relatively long. Similarly, depending upon the particularimplementation and intended use, the tube can be rigid along its entirelength, flexible along a portion of its length, or configured forflexure at only certain specified locations.

In one embodiment, tube 502 may be flexible, adapted for flexiblesteering within bodily lumens, as understood in the art. For example,tube 502 can be steered with controls to move at least a portion,generally distal end 504, up and down, or side-to-side. Additionaldegrees of freedom, provided for example via rotation, translationalmovement of tube 502, or additional articulation of bending sections,are also contemplated. In such an embodiment, resection device 500 maybe provided with suitable steering systems for, among other things,articulating or steering distal end 504 of tube 502. For example, asuitable steering system may include one or more of pulleys, controlwires, gearing, electrical actuators (such as servomotors), pneumaticactuators, and the like.

Such flexible tubes may be formed of any suitable material havingsufficient flexibility to traverse body cavities and tracts. Suitablematerials may include synthetic plastics, fiber, or polymers such aspolyesters. Alternatively, tube 502 may be rigid or semi-rigid, formedfrom materials such as stainless steel or the like, includingsuper-elastic or shape-memory alloys such as nitinol. Tube 502 may alsobe manufactured from any biocompatible material such as a sheath, withor without a PTFE outer layer.

Moreover, the tube 502 and EMR cap assembly 100 may be designed toimpose minimum risk to the surrounding tissues while in use. To thisend, the proximal or distal ends of these components may includegeometrical structures, such as rounded or beveled terminal ends orfaces, to reduce trauma and irritation to surrounding tissues. Further,the outer surface of the EMR cap assembly and tube may include anysuitable coating or covering. For example, the outer surface may includea layer of lubricous material to facilitate insertion through a bodylumen or surgical insertion. The distal end may be comprised of orinclude a soft polymer or other material, such as silicone or rubber, tohelp cushion the device on tissue as well as to help seal any vacuumused.

To effectively maneuver the tube 502 within a body cavity, the operatorshould know the exact location of the tube in the cavity at all times.To this end, one or more portions of resection device 500 may beradiopaque, produced by inclusion of material such as barium sulfate inplastic material or one or more metal portions, which provide sufficientradiopacity. Alternatively, the distal end of the tube or EMR capassembly may include a radiopaque marker or sonoreflective marker (notshown). These markings facilitate detection of a position and/ororientation of tube 502 within the patient's body, and a surgeon, withthe aid of suitable imaging equipment, may track the path followed bythe endoscope system and avoid potential damage to sensitive tissues. Inother embodiments, device 500 is designed to fit through a workingchannel of an endoscopic device and may be observed through theendoscopic device. Alternatively, the device 500 may be deliveredadjacent to or over the endoscopic device.

To inhibit bacterial growth in the body cavity or in the mucosal wall,resection device 500 may be coated with an anti-bacterial coating. Thecoating may contain an inorganic antibiotic agent, disposed in apolymeric matrix, which adheres the anti-biotic agent to the device'ssurface. Further, a drug releasing coating may also be applied to theouter surface of resection device 500, assisting in healing. In furtherembodiments, the resection device may be constructed from materialimpregnated with suitable antibiotic or therapeutic agents.

As discussed, tube 502 may include one or more channels. A typicalconfiguration may include one or more working channels, such as aresection loop channel. Based on the application, other channels, suchas a scope channel or a camera channel, may also be present. Throughthese channels, the operator may introduce one or more medical devicesto extend out of the distal end of tube 502. For example, during aresectomy, the operator may introduce a cautery device into one workingchannel, and introduce a resection loop into another working channel,the resection loop channel. In some embodiments, the operator mayintroduce, for example, a hot grasper, an injection needle or a suctiondevice into one working channel. Additionally, from time to time duringthe procedure, the operator may insert, for example, a light source, acamera, an injector, or a morcellator within a working channel. Thedistal ends of these channels may coincide with the working channel andresection loop channel of EMR cap assembly 100 while their proximal endmay be coupled to the distal end of handle 510. In other embodiments,light sources and optics, such as a cameras, may be integrated into thewalls of the tube. Optics may be integrated in the wall of the tube fromthe proximal end to the distal end. In other embodiment, wireless opticmeans may be integrated only in the distal end walls of the tube.

The proximal end 506 of tube 502 can be coupled to handle 510 forgripping by an operator such as a surgeon, while the distal end 106remains open for medical devices to extend out. The handle 510 can beattached to tube 502 by, for example, welding, use of an adhesive, orintegrally forming with tube 502.

Handle 510 may include one or more ports 512 to introduce medicaldevices into the working channels of the tube. Moreover, vacuum pumps orirrigation feeds may be attached to port 512 to generate a suction forceat the distal end of the tube, or deliver irrigation fluid to thedesired location within a patient's body, respectively. Handle 510 mayinclude the ability to steer the distal end of the resection device.Further, the handle portion may include an actuating mechanism toactuate one or more medical devices at the distal end of the elongatetube. For example, the handle may include an actuating mechanism toactuate and close the resection loop at the distal end of the resectiondevice. Similarly, it may include a mechanism to power on or off thesuction device attached to its working channel. The handle may furtherinclude a coating or covering of a soft polymer or other material toimprove grip or ergonomics.

The EMR cap assembly 100 may be coupled to the distal end of the tube502. In one embodiment, the EMR cap assembly 100 may be detachablyattached to the distal end of the tube 502 using any known couplingtechnique such as snap-fitting, friction fit, luer-lock, screwthreading, etc. Before inserting the tube within a patient's body, theEMR cap assembly may be snapped on. Alternatively, the EMR cap assemblymay be permanently coupled to the distal end of the tube. Techniquessuch as gluing, welding, or sealing may be used.

Further, a swivel mechanism may be introduced between the tube 502 andthe EMR cap assembly 100, such that the EMR cap assembly 100 may easilyswivel to make a greater surface contact with a lesion and swiveltowards the lesion. In some embodiments, the cap will swivel uponcontact with tissue to allow alignment of the opening of the cap. Inother embodiments, the cap may be controllably rotated for aligning thecap opening. Any suitable swivel mechanism may be used without departingfrom the scope of the present disclosure.

In other embodiments, the tube and the EMR cap assembly may be shapedsuch that the EMR cap assembly may be inserted into the lumen of thetube until it extends out from the distal end of the tube. Here, thediameter of the tube 502 and the EMR cap assembly 100 may taper from theproximal end to the distal end, such that the distal diameter of thetube 502 is lesser than the proximal diameter of the EMR cap assembly100. In this situation, when the EMR cap assembly 100 is pushed to thedistal end, its proximal portion engages with the distal opening of thetube, wedging it in place.

It will be understood that other techniques to engage the proximal endof the EMR cap assembly with the distal end of the elongate tube may becontemplated without departing from the scope of the present disclosure.For example, magnetic connection may be possible between the distal tubeopening and the proximal EMR cap assembly opening.

Exemplary Resection Method

FIGS. 6A-6F illustrate a method for resecting lesions or polyps ortissue from a patient's body. A typical location for a resection of thissort is the esophagus, and that location will be discussed here. As willbe understood by those in the art, other patient locations would beequally suitable. An endoscopic device including the cap assembly may beinserted into the body lumens either through a percutaneous incisionproviding access to the esophagus, or through a natural opening, such asthe mouth. Once inserted, the resection device 500 is advanced towards alocation on a mucosal wall 602. A light source and a camera may beinserted in the working channel to direct the device within theesophagus, and to spot the lesions. Alternatively, polyps and lesionsmay be identified by any suitable means prior to inserting resectiondevice 500 into the patient. Pedunculated polyps may be easilyidentified within the esophagus. Low-lying and flat lesions, however,may be harder to discover. To detect these lesions, a biomarker or dyemay be sprayed in the esophagus. Cancerous lesions emit a differentwavelength when light falls on them, allowing operators to easily detectthem.

In the illustrated embodiment, EMR cap assembly 100 is coupled to thedistal end of elongate tube 502, such as an endoscope, when theprocedure begins. Alternatively, EMR cap assembly 100 may be actuated toextend out of the distal end of the tube 502 when required. As shown,the distal end of the EMR cap assembly 100 may then be placed over orproximate a lesion 604. In case the lesion is situated at an unreachableposition within the body, EMR cap assembly 100 may swivel to attaincontact with the lesion and/or surrounding tissue. This position isdepicted in FIG. 6B.

Next, suction is applied to a working channel of the tube 502 andthereby to the working channel 202 of the EMR cap assembly 100 unit. Thesuction force draws the lesion 604 into the working channel 202 of theEMR cap assembly 100 (FIG. 6C). In other embodiments, other tools suchas graspers, pincers, baskets or the like may be used to draw in thetissue. In one embodiment, if the lesion is too flat along theesophageal wall, the lesion may be injected with a saline solution orany other suitable solution to create a buffer layer between the lesionand that wall. With the lesion sufficiently raised off the esophaguswall, suction may be more easily accomplished. In various embodiments,instruments such as needles are easily insertable and utilized at thetissue site.

Once the lesion 604 is forced into the working channel 202 of the EMRcap assembly 100, the trigger line 140 may be pulled proximally, inorder to deploy a first ligation band 122 off of the distal end of thecap structure. When this happens, the first ligation band 122 constrictstoward its relaxed, unstretched condition, and the constriction of theligation band 122 around the tissue forms a pseudo polyp, as shown inFIG. 6D. The ligation band 122 remains around the tissue forresectioning (although, for clarity, the ligation band is not shown inFIGS. 6E and 6F).

In some embodiments, the suction device may be powered off or removed,and the area may be visualized. For example, lesion 604 may be examinedto determine whether it is cancerous or not. Various techniques may beemployed for this determination. In one embodiment, a fluorescent orbiomarker dye may be sprayed on lesion 604. If lesion 604 is cancerous,it will emit a particular color. Based on the emitted or projectedcolor, physicians can determine whether the lesion is benign orcancerous. Alternatively, by looking at lesion 604 under the microscope,physicians can make this decision. With the suction released, properpositioning of the resection loop track 112, and thereby the resectionloop 402, may be confirmed. This can include a confirmation check thatno muscularis is within the area to be resected by the resection loop402. The resection loop 402 (not shown in FIGS. 6A-6F) may be extendedinto the resection device track 112 at any step prior to its use, eitherbefore or after deployment of a ligation band. A tissue sample could bewithdrawn via a needle, biopsy forceps or the like to help diagnose thetissue prior to use of the ligation bands or resection loop.

With the cap assembly placed into proper position over the bandedtissue, which thereby positions the resection loop track 112 andconsequently the resection loop 402 into proper position over the bandedtissue, the proximal end of the resection loop 402 may be pulledproximally. This causes the resection loop 402 to begin closing bywithdrawing into track 112, reducing the resection loop's diameter intrack 112, and trapping lesion 604. Subsequent pulling may contractresection loop 402 further, forming a tightened grip around lesion 604.

The resection loop may be a cauterizing resection loop providingelectrical energy to the trapped portion of the lesion 604, andresecting it off the esophagus wall (as shown in FIG. 6E). Withmodifications in the EMR cap assembly 100 device, the electro-cauterydevice may be replaced with a laser device that heats the resection loopto resect the lesion. In some embodiments, the cap itself may haveelectrocautery capability, such as electrodes in the cap. Otherresecting means may be contemplated, which will lie within the scope ofthe present disclosure.

Once the lesion is resected, the device may carry out any one of anumber of procedures to remove the resected matter. For example, theresection device 500 may extract lesion 604 or morcellate it and thenextract it. For extraction, any retrieval device known now or later maybe employed. In one embodiment, the lesion 604 may be extracted with thehelp of suction force applied at the proximal end of the resectiondevice 500 (FIG. 6F). In another embodiment, a basket, a grasper, orpincers may be used. These devices may be self-expandable or may expandby some actuation mechanism incorporated in the resection device'shandle 510. The retrieval device may be inserted in a collapsed statethrough the proximal end of the tube 502; and it may extend out of thedistal end 106 of the EMR cap assembly's working channel 202 in anexpanded state. Once the device is placed over the resected lesion, itmay be actuated to close in on the lesion, trapping it. Subsequently,the entire resection device 500 may be withdrawn from the patient'sbody. In another embodiment, the end of the inner cap may be flexible.After resection, the end of the cap may be actuated to close over theresected lesion, trapping it and subsequently removing it from thepatient's body.

If lesion 604 is too large to fit in working channel 202 or to begrasped in the other retrieval tools, it may be morcellated prior toextraction. A morcellator (not shown) may be introduced in workingchannel 202 along with a suction device. The suction device holds lesion604 around the opening of the EMR cap assembly 100, while themorcellator breaks lesion 604 into smaller pieces. Subsequently, theretrieval devices suction or extract the pieces.

The use of multiple ligation bands 122, 124, 126, 128 allows the deviceto be repositioned for capturing additional tissue with sequentialdeployment of the bands without having to withdraw the device from thepatient. Thus, after repositioning of the device to position the capassembly adjacent a second target site, a second actuation of thetrigger line 140 may cause the second ligation band 124 to be deployedoff of the distal end 107 of the outer cap 104. Then, after furtherrepositioning, a third actuation of the trigger line 140 may cause thethird ligation band 126 to be deployed off of the distal end 107 of theouter cap 104, and, after further repositioning, a fourth actuation ofthe trigger line 140 may cause the fourth ligation band 128 to bedeployed off of the distal end 107 of the outer cap 104. Theresectioning of a banded tissue section may be performed after thatparticular tissue section has been banded and before the next tissuesection is banded. Alternatively, multiple tissue sections may be bandedsequentially without intermediate resectioning, and subsequently theresectioning may be performed on one or more of the banded tissuesections.

In alternate embodiments, the device may be used in the followingmanner. The cap assembly may be positioned adjacent tissue to beresected. Then, the tissue may be drawn within the cap assembly. Then, aresection loop may be deployed around the tissue without severing thetissue. The tissue may be evaluated to see if there are any issues withcarrying out full resectioning with the loop, for example if there isany muscularis ensnared by the loop. If there are no such issues, fullresectioning may be carried out with the loop. If an issue such asensnared muscularis is presented, the loop could be released, releasingthe tissue. Subsequently, a ligation band could be deployed around thetissue. The ligation band deployment may be advantageous in that theband may squeeze out any muscularis. Then the resection loop may bedeployed for resectioning of the tissue captured by the ligation band.

In certain embodiments, the proximal end of the cap may be flexibleenough to allow the cap to bend at an angle to the endoscope. Thisbending may allow better positioning of the cap opening around tissue.In some embodiments, the cap may bend or rotate with the assistance oftensioning or steering filaments or wires or other steering means. Thedistal end of the cap may extend or be sloped at any suitable angle withrespect to the longitudinal axis of the endoscope.

The resection loop may be resettable. For example, it may be configuredsuch that it may be advanced distally into the resection device trackmultiple times. In some embodiments, the resection loop may beresettable by use of a tensioning filament or wire attached to the loopopposite the location of the filament or wire used to actuate theresection loop. The operator can use the resetting filament or wire topull or redeploy the resection loop back into position to allow morethan one resectioning while the device is in a useful position.

It will be appreciated that certain embodiments described hereincomprise a tissue resection cap assembly secured to the distal end of anendoscope, but similar embodiments may also be configured to be securedto the distal end of any other suitable type of elongated medical devicehaving a working channel, such as cystoscopes, duodenal scopes,colonoscopes, guide tubes, introducers, catheters with lumens, and thelike.

It will be appreciated from the disclosure herein that variousembodiments of the invention can improve the speed and accuracy of theprocedures desired to be performed. For example, ligation bands can bedeployed and a resection loop may be actuated without having to withdrawthe endoscope or other elongated medical device. Various embodiments mayalso help avoid the time it would take to preset a snare or loop tomatch the opening of a cap. Having the cap structure include a resectiondevice channel and a resection device track in communication with theresection device channel can help lead the snare or loop to the correctposition and can help improve speed and accuracy. With variousembodiments of the invention, the deployment of the resectioning loopcan be performed simultaneously with or immediately after or beforeligation band deployment, without the need for switching orrepositioning devices.

Embodiments of the present disclosure may be used in any medical ornon-medical procedure, including any medical procedure where monitoringof an organ's activity is desired. In addition, at least certain aspectsof the aforementioned embodiments may be combined with other aspects ofthe embodiments, or removed, without departing from the scope of thedisclosure.

Other embodiments of the present disclosure will be apparent to thoseskilled in the art from consideration of the specification and practiceof the embodiments disclosed herein. It is intended that thespecification and examples be considered as exemplary only, with a truescope and spirit of the invention being indicated by the followingclaims.

What is claimed is:
 1. A tissue resection cap assembly configured to be secured to a distal end of an elongated medical device having a working channel, the cap assembly comprising: a cap structure comprising a proximal end, a distal end, an outside surface, and a working channel extending from the proximal end to the distal end; at least one ligation band positioned on the outside surface of cap structure; and a trigger line for deploying said at least one ligation band from the distal end of the cap structure; wherein the cap structure further comprises a resection device channel and a resection device track in communication with the resection device channel; wherein a proximal end of the resection device channel is adapted for communication with the working channel of the elongated medical device; wherein the resection device channel extends distally to the resection device track adjacent the distal end of the cap structure; and wherein the resection device track substantially surrounds the working channel of the cap structure adjacent the distal end of the cap structure.
 2. The cap assembly of claim 1, wherein the cap structure comprises a first cap and a second cap, wherein the first cap defines the resection device channel, and wherein the second cap is configured to receive at least a portion of the first cap.
 3. The cap assembly of claim 2, wherein a distal portion of the first cap and a distal portion of the second cap cooperate to define the resection device track.
 4. The cap assembly of claim 3, wherein the resection device track extends at an angle to the resection device channel.
 5. The cap assembly of claim 2, wherein the resection device channel further includes a resection wire lumen.
 6. The cap assembly of claim 2, wherein the first cap further defines the working channel of the cap structure, extending from the distal end to the proximal end of the first cap.
 7. The cap assembly of claim 2, wherein a portion of the resection device channel is defined by an outer wall of the first cap.
 8. The cap assembly of claim 7, wherein the resection device channel further includes a section disposed within the first cap.
 9. The cap assembly of claim 2, wherein the distal end faces of the first and second caps are angled relative to a longitudinal axis of the cap assembly.
 10. The cap assembly of claim 1, wherein a portion of the resection device channel is configured to prevent distal movement of a portion of a resection device.
 11. The cap assembly of claim 10, wherein the portion of the resection device is a sheath.
 12. The cap assembly of claim 1, wherein the cap assembly is configured to bend relative to the distal end of an endoscope.
 13. The cap assembly of claim 1, wherein the resection device track is adapted for receiving a distal resection loop portion of a resection device.
 14. The cap assembly of claim 1, wherein the resection device comprises a resection loop.
 15. The cap assembly of claim 14, wherein the resection loop comprises an electrocautery tool.
 16. A resection device comprising: a first part defining a resection device channel, wherein the first part includes a distal end having a first opening; a second part configured to receive at least a portion of the first part, wherein the second part includes an outside surface and a distal end having a second opening, wherein a distal portion of the first part and a distal portion of the second part cooperate to define a resection device track for receiving a resection device; at least one ligation band positioned on the outside surface of the second part; and a trigger line for deploying said at least one ligation band from the distal end of the second part.
 17. A method of resecting tissue comprising: attaching a cap assembly to the distal end of an elongated medical device having a working channel, the cap assembly comprising: a cap structure comprising a proximal end, a distal end, an outside surface, and a working channel extending from the proximal end to the distal end; at least one ligation band positioned on the outside surface of cap structure; and a trigger line for deploying said at least one ligation band from the distal end of the cap structure; wherein the cap structure further comprises a resection device channel; and wherein a proximal end of the resection device channel is adapted for communication with the working channel of the elongated medical device; positioning the cap assembly adjacent tissue to be resected; drawing tissue within the cap assembly; actuating the trigger line to deploy a ligation band around the tissue; and actuating a resection device to cut the tissue.
 18. The method of resecting tissue of claim 17, wherein the step of attaching the cap assembly to the distal end of the elongated medical device includes the step of aligning the resection device channel with a working channel of the elongated medical device.
 19. The method of resecting tissue of claim 17, wherein after the step of actuating the trigger line to deploy a ligation band and prior to the step of actuating the resection device to cut the tissue, the tissue is released to allow confirmation of proper positioning of the resection device.
 20. The method of resecting tissue of claim 17, wherein the cap assembly further comprises a channel for allowing the trigger line to extend from a working channel of the cap structure to the outside surface of the cap structure without having the trigger line extend through a resection loop of the resection device. 